| France likely to adopt T-DMB and DAB+ systems for digital radio29th March 2007 The French Minister for Industry François Loos has given a speech in which he said that T-DMB and (possibly) DAB+ should be used as the terrestrial digital radio system(s) in France. (Google's automated English translation). The French media regulator, the CSA, now has to decide whether to use T-DMB alone or whether to use both T-DMB and DAB+ for terrestrial digital radio. The following two paragraphs contain the relevant quotes, which someone has kindly translated for me:
The Minister also said that the European Satellite Digital Radio (E-SDR) and DVB-SH systems have been selected as options for the satellite radio system that will transmit in L-band, and DRM has been selected for the digital replacement for AM. Then on Thursday 15th March, the Digital Radio Organisation in France issued a press release where they sounded quite optimistic that DAB+ will be chosen as well as T-DMB:
The CSA is expected to make up its mind about which system(s) to use in the next few weeks.
T-DMB Whereas most readers will know that DAB+ is the upgraded version of the DAB digital radio system, many might not know what T-DMB is, so I'll give a brief explanation below -- for a more in-depth look at T-DMB, this page compares it with DAB+. T-DMB (Terrestrial - Digital Multimedia Broadcasting) is a DAB-based system that was designed to carry mobile TV, but can also carry digital radio. T-DMB and DAB+ are almost identical in terms of the main technologies they use to carry radio stations, as both systems are based on the old DAB system but add the AAC+ audio codec and Reed-Solomon error correction coding to make the systems far more efficient than DAB. As T-DMB and DAB+ are so similar, the DAB receiver module companies that produce around 95% of all DAB receiver modules, Frontier-Silicon and Radioscape, have already said that they plan to add support for T-DMB to their DAB/DAB+ modules that are coming out in the next few months. Using T-DMB for digital radio has a few drawbacks, however, and even WorldDMB, the organisation in charge of DAB, DAB+ and T-DMB says that "DMB is designed and optimised for mobile television, but it is not recommend for radio services". It says this partly because it lacks features such as scrolling text that DAB+ offers, and also because it wastes bandwidth on overhead. As T-DMB was primarily designed to carry mobile TV, it has to support video decoding that obviously isn't needed for radio stations, and this support for video wastes about 10 - 15% of a radio station's bandwidth on overhead which is required to synchronise the video and audio for mobile TV channels. Also, when the T-DMB specification was written, WorldDAB (as it was called then) laughably required that video be sent with an AAC+ stream (at the time, WorldDAB was still furiously trying to convince all countries to adopt the old DAB system, so it deliberately made it difficult for radio stations to use AAC+ on T-DMB), so radio stations on T-DMB have to transmit a video stream with nothing in it or just displaying a station logo, which consumes a minimum of 4 kbps of bandwidth -- radio stations can't transmit proper video alongside the audio, because video uses far higher bit rates than audio, so there isn't enough capacity available to do this. T-DMB also supports graphics streams, using the MPEG-4 BIFS (Binary Format for Scenes) specification, which "has been designed to allow for the efficient representation of dynamic and interactive presentations". MPEG-4 BIFS data could also be transmitted over DAB+ in a data
channel, however, but it would lack the ability for the graphics to be
displayed synchronously with the audio.
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